I recently scored this nice little MTH Premier switcher, and on it's first run out, it stalled on a pair of switches in a staging yard. Bummer, that's what switchers are for! So, I took a look and of course, the reason is obvious, no rollers on the locomotive, only a pair on the tender. There were some holes in the frame for the standard MTH roller hardware, so it seemed like it would be an easy upgrade.
WAIT, they used the roller pickup wire in the tether for the front coupler! Bummer, no way to get the power back to the electronics in the tender. Not to be deterred, I fell back to my normal fix for Lionel IR tether locomotives, a separate tether wire. So here it is in pictures.
First step, mount the MTH roller, the BD-0000042 is the shortest one they have, and it just fits. It was a bit tricky inside as they didn't intend to install rollers and mounted stuff above the mounting holes. After removing some things, I was able to get a roller and wire installed. I did have to grind down the inside roller insulator to get it into place. The clearance is small in the roller well, and when the roller is fully depressed, it can contact the locomotive frame. To protect against that, I stuck a piece of Kapton tape in there to insulate it. The parts used were the BD-0000006 and the BD-0000009 roller pick-up insulators along with the BD-0000042 roller. I don't happen to have the number of the hex post that secures these handy...
The red wire is from the roller pickup, it goes through a 1.8A trip PTC to protect the wire. This is in case of a derailment or the tether pin getting shorted to something when not plugged in. That shouldn't happen, but then things seem to happen when you least expect them to.
Here's the two tether pieces, I use machine socket parts to create the tether. The tender end is tapped directly into the roller wire in the tender and routed down to mate with the locomotive wire. I used a piece of clear heatshrink to secure the power wire to the "wireless" drawbar.
Here they are lashed up, it's hardly noticeable that something has been added. Now it has no issue at all going over switches, job done!
Hope this helps someone in the same boat. It's a nice little switcher, and now it can actually perform it's intended purpose.